學術資源整合系統-相關推薦

 
作者Huang, H.-D.
出版日期2010
著作名稱Mass aggregation for reproduction by a gymnodoridid nudibranch, Gymnodoris ceylonica (Kelaart, 1858), in Lanyu (Orchid Is.), Taiwan.
摘要Widely distributed in Indo-Pacific area, translucent white Gymnodoris ceylonica is moderately common and usually found in seagrass or algae zones preying other invertebrates (Debelius and Kuiter, 2007). Observation by divers showed this species swim from 30m up to 10m deep for reproduction. Incidentally encountered in mid-July 2009, a mass aggregation for reproduction by G. ceylonica was observed at Lanyu (Orchid Is.), southeastern Taiwan. Estimated more than 30 individuals occurred in a 20 by 20m reef flat with sandy bottom at 4-8 m deep. Sizes of G. ceylonica individuals ranged from 50 to 80 mm. Over 70% of G. ceylonica at the site were ovigerous, judged by the yellow eggs through their translucent body wall. During the observation in approximately 60 minutes, approximately 60% individuals were mating or laying eggs. Mating pairs copulated with everted bifurcate sex organs at the right side of the body for reciprocal fertilization. Gymnodoris ceylonica deposited light-yellowish messy egg string masses instead of the spiral bands like most other dorid nudibranchs do. At the site, no G. ceylonica was foraging; some individuals found weak or dead without eggs inside the body. Few animals in the area fed on eggs of G. ceylonica, yet some eggs may be captured by filter feeders on the sea bottom.
系統號NO000004194

May 10 2024 17:17:25
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